```

...that's because the client generator uses the OpenAPI internal **operation ID** for each *path operation*.

OpenAPI requires that each operation ID is unique across all the *path operations*, so FastAPI uses the **function name**, the **path**, and the **HTTP method/operation** to generate that operation ID, because that way it can make sure that the operation IDs are unique.

But I'll show you how to improve that next. 🤓

And we can add a list of `dependencies` that will be added to all the *path operations* in the router and will be executed/solved for each request made to them.

!!! tip

│   ├── main.py
│   └── test_main.py
```

Let's say that now the file `main.py` with your **FastAPI** app has some other **path operations**.

It has a `GET` operation that could return an error.

It has a `POST` operation that could return several errors.

Both *path operations* require an `X-Token` header.

=== "Python 3.10+"

    ```Python
    {!> ../../../docs_src/app_testing/app_b_an_py310/main.py!}

### Top-level application

First, create the main, top-level, **FastAPI** application, and its *path operations*:

```Python hl_lines="3  6-8"
{!../../../docs_src/sub_applications/tutorial001.py!}
```

### Sub-application

Then, create your sub-application, and its *path operations*.

    It is the "**path operation decorator**".

You can also use the other operations:

* `@app.post()`
* `@app.put()`
* `@app.delete()`

And the more exotic ones:

* `@app.options()`
* `@app.head()`
* `@app.patch()`
* `@app.trace()`

!!! tip
    You are free to use each operation (HTTP method) as you wish.

## Order matters

When creating *path operations*, you can find situations where you have a fixed path.

Like `/users/me`, let's say that it's to get data about the current user.

And then you can also have a path `/users/{user_id}` to get data about a specific user by some user ID.

### Use your tags

Use the `tags` parameter with your *path operations* (and `APIRouter`s) to assign them to different tags:

```Python hl_lines="21  26"
{!../../../docs_src/metadata/tutorial004.py!}
```

!!! info
    Read more about tags in [Path Operation Configuration](path-operation-configuration.md#tags){.internal-link target=_blank}.

### Check the docs

            ),
        ] = None,
        scopes: Annotated[
            Optional[Dict[str, str]],
            Doc(
                """
                The OAuth2 scopes that would be required by the *path operations* that
                use this dependency.
                """
            ),
        ] = None,
        description: Annotated[
            Optional[str],
            Doc(
                """

Doing this, our `GzipRequest` will take care of decompressing the data (if necessary) before passing it to our *path operations*.

After that, all of the processing logic is the same.

But because of our changes in `GzipRequest.body`, the request body will be automatically decompressed when it is loaded by **FastAPI** when needed.

# レスポンスモデル

*path operations* のいずれにおいても、`response_model`パラメータを使用して、レスポンスのモデルを宣言することができます:

* `@app.get()`
* `@app.post()`
* `@app.put()`
* `@app.delete()`
* など。

```Python hl_lines="17"
{!../../../docs_src/response_model/tutorial001.py!}
```

!!! note "備考"
    `response_model`は「デコレータ」メソッド（`get`、`post`など）のパラメータであることに注意してください。すべてのパラメータやボディのように、*path operation関数* のパラメータではありません。